Stabilizing jack base



Feb. 3, 1970 R. c. BRAMMER 3,

STABILIZING JACK BASE 2 Sheets-Sheet 1 Filed Oct. 30, 1967 ATTORNEYSFeb. 3, 1970 R. c. BRAMMER STABILIZING JACK BASE 2 Sheets-Sheet 2 FiledOct. 30, 1967 IN VEN TOR BEAM 765? ATTORNEYS United States Patent3,493,209 STABILIZING JACK BASE Robert C. Brammer, Traverse City, Mich.,assignor to Stromberg-Carlson Products, i Inc., Traverse City,

Mich., a corporation of Michigan Filed Oct. 30, 1967, Ser. No. 679,121Int. Cl. B66t 13/00; E04g 25/00; F16m 13/02 US. Cl. 248352 8 ClaimsABSTRACT OF THE DISCLOSURE This disclosure relates to a base support fora leveling jack which employs a threaded rod and nut which rests on topof the base. A vertically extending hole in the top surface of the baseis provided for the threaded rod. The base further comprises amulti-sided wall structure with a flange at the bottom portion thereof.Preferably, each side wall has a central portion cut out. The Wallstructure is reinforced through ribs which'extend upwardly from thebottom flange and/or downwardly from the top surface at the corners ofthe side walls. The base support is preferably integrally formed from amoldable plastic.

Stabilizing jacks are generally used for supporting the sides of campingtrailers and coaches. These jacks comprise a base support with athreaded rod and nut which rest on the top of the base with the end ofthe rod extending through a hole in the top of the base support. The topof the rod has a supporting surface. The jack is adjusted by turning thenut. conventionally, bases are made from steel or other structural metalbecause of the load requirements.

For lighter applications, it has been found that certain aluminums canbe employed for the bases. In order to make the bases as light aspossible, the central portions are cut out of the sides. It was thoughtthat the bases could be cast in one piece without the central portions.However, it was found that sharp edges and burrs remained on the sidewalls after the casting of the bases. These sharp edges and side wallsmake gripping of the base at the corners through the holes in the sidewalls quite dangerous.

It would be desirable to make the base out of a light weight plasticmaterial. However, with the same configuration as the metal, sides arenot strong enough to support the loads. The base usually fails at thecorners at the side walls wherein buckling occurs.

I have now discovered a base construction for stabilizing jacks whichconstruction is light in weight and strong enough to support therequired loads. The construction allows the use of light weight plasticand the side walls can be cut out in the central portions thereof for alighter weight construction and for gripping without cutting of thehands.

By various aspects of this invention one or more of the followingobjects can be obtained.

It is an object of this invention to provide a base for a stabilizingjack which is strong in construction and light in weight.

It is a further object of this invention to provide a base for astabilizing jack having an open sided configuration forming handgripping areas wherein there are no jagged edges at the gripping area;

It is a further object of this invention to provide a base constructionfor stabilizing jacks which satisfy strength requirements and can bemade from a multiple plastic material.

It is a still further object of this invention to provide a nestable andstackable base construction for stabilizing jacks which have handgripping areas and satisfies 3,493,209 Patented. Feb. 3, 1970 'ice thestrength requirements even when made from a moldable thermoplasticmaterial.

It is still another object of this invention to provide an injectionmolded thermoplastic base construction for a stabilizing jack whichsatisfies strength requirements by integrally molded strengtheningmeans.

Other aspects, objects, and several advantages of this invention areapparent to one skilled in the art from a study of this disclosure, thedrawings, and the appended claims.

According to the invention, there is provided a base for stabilizingjack comprising a multi-sided configuration, each side wall having atrapezoidal configuration. The base also has a continuous bottom flangeextending laterally of the side wall, and a top wall integrally formedwith the side walls and having a vertically extending hole therein. Thebase according to the invention has a reinforcing rib between the bottomflange and the junction of at least two of the side walls extendingupwardly from the bottom flange. Alternately or additionally, the basehas a reinforcing rib which is integrally formed of thickened materialextending downwardly from the upper surface and positioned between thejunction of at least two of the side walls.

In a preferred embodiment of the invention, a reinforcing rib extendsupwardly from the bottom flange and a reinforcing rib extends downwardlyfrom the top surface between each of the side walls. In this embodiment,the ribs preferably overlap to provide a completely strengthened cornerfor the jack.

The invention will now be described with reference to the accompanyingdrawings in which:

FIG. 1 is a perspective view of a stabilizing base and jack according tothe invention;

FIG. 2 is a top plan view of the base without the threaded rod shown inFIG. 1;

FIG. 3 is a sectional view along lines liIL-III of FIG. 2;

FIG. 4 is a sectional view along lines IV-IV of FIG. 3; and

FIG. 5 is a sectional view along lines V-V of FIG. 3.

Referring now specifically to the drawings, a base 2 supports a threadedrod 4 having a supporting surface 6 through a nut 8 which rests on thetop portion of the base 2. The nut 8 threadably engages rod 4 and can beturned by handle '10 to raise or lower the supporting platform 6.

The base comprises a plurality, preferably 4, side walls 12 which aregenerally of trapezoidal configuration. A flange 14 extends laterallyoutwardly and continuously around the bottom portion of the side walls12.

The top surface 16 of the base in integrally formed with the side walls12. The threaded rod extends through a vertical hole in the top surface16 formed by a vertical tube 18 which extends downwardly substantiallybelow the top surface 16. Generally, the height of tube 18 will be aboutone-fifth of the height of the base. The top portion of tube 18 extendsslightly above the top surface 16 of the base at 19 to provide thesupporting surface for the nut 8. The stress on tube 18 is transmittedto the corners of the base through ribs 22 which are integrally formedof thickened material with the base. The ribs 22 connect the corners ofthe side walls with the tube 22 and extend downwardly a substantialdistance toward the bottom of the side walls.

The side walls are cut out at 20 to reduce the weight and material costof the base. Further, the cut out portions provide hand gripping areasat the corners of the side walls. If the base is injection molded from athermoplastic material, such as polystyrene, the edges of the side wallsat the cut out portions 20 will not be sharp and will not cut when thecorners are gripped.

Strengthening the side walls is a rib 24 extended upwardly from flange14 at the outer portion of the corners. The rib 24 is integrally formedwith the base and overlaps the downwardly extending rib 22 as best seenin FIG. 3. This overlapping configuration of ribs 22 and 24 adequatelystrengthen the side walls at the load bearing corners so that the basecan be molded from a moldable thermoplastic material.

Whereas the invention has been described with reference to a particularconfiguration, it is obvious that within the scopeof the invention otherconfigurations can be used. For example, the described configuration hasrib 24 on the outside of the base. In this configuration, the bases areeasily stackable and nestable. However, if this type of a base was notdesired, it is within the scope of the invention to extend flange 14inwardly instead of outwardly and to provide a supporting flange on theinner corners of the side walls 12. In this instance, the lower rib 24would then join the upper rib 22.

In a preferred embodiment of the invention, the base is injection moldedfrom a polystyrene material. A specific example of a styrene which canbe used is high impact Bakelite, PMD6500.

Reasonable variation and modification are possible within the scope ofthe foregoing disclosure and the drawings, without departing from thespirit of the invention.

I claim:

1. A base for a jack comprising a plurality of side walls integrallyconnected, each side wall having a continuous bottom flange extendinglaterally outwardly thereof, a top wall integrally formed with said sidewalls, said top wall having a vertically extending hole therethrough, afirst reinforcing rib of thickened material integrally formed with saidbase between said bottom flange and at least one junction of two sidewalls extending upwardly from said bottom flange, a second reinforcingrib of thickened material integrally formed with said base and extendingdownwardly from said top wall on an inner portion of said one junction,said first and second ribs being shaped and extending along saidjunction so as to provide substantially uniform reinforcing strengthfrom said bottom flange to said top wall.

2. A base according to claim 1 wherein said first reinforcing rib tapersupwardly and overlaps with said second reinforcing rib and said secondreinforcing rib tapers 4 downwardly.

3. A base according to claim 1 wherein the central portions of at leasttwo adjacent side walls are cut out so as to form a handle grip at thecorners of said side walls.

4. A base according to claim 3 wherein there are four side walls, eachside wall has a central portion thereof cut out to form a handlegripping area.

5. A base for a jack comprising a plurality of side walls, a top wallintegrally formed with'said side walls and having a vertically extendinghole therethrough, a vertically extending tube formed around said holeand extending beneath saidtop wall, a reinforcing rib integrally formedof thickened material beneath said top wall between at least onejunction of two of said side walls on the inner surfaces thereof andsaid vertically extending tube, said reinforcing rib extendingdownwardly along said junction from said top wall.

6. A base according to claim 5 wherein said rib extends downwardly alongthe inner surface of said junction below the bottom portion of saidtube.

7. A base according to claim 5 further comprising a continuous outwardlyextending flange at the bottom of said side Walls, a reinforcing ribbetween the junction of said two side walls at an outer portion thereofand extending upwardly from a bottom portion thereof, said outerreinforcing rib tapering upwardly and said inner rib tapering downwardlysuch that the combined strength from said reinforcing ribs issubstantially uniform from said flange to said top wall.

8. A base according to claim 7 wherein said base is integrally formedfrom a synthetic plastic material.

References Cited UNITED STATES PATENTS 483,487 9/1892 Wild 254981,507,625 9/1924 Runyan 25498 1,794,052 2/1931 Anderson et a1 248-3521,894,293 1/1933 Green 248352 3,232,584 2/1966 Miles 248-352 X 3,329,4027/1967 Grumman 248-357 X ROY D. FRAZlER, Primary Examiner J. F. FOSS,Assistant Examiner US. Cl. X.R.

